{"schema_version":"1.2","pwsid":"IL1410400","system_name":"OREGON","city":"OREGON","state":"IL","population_served":3449,"source_type":"GW","summary":"OREGON serves approximately 3,449 people in OREGON, Illinois. Based on contaminant analyses from DNR, WQP, EPA ECHO, EPA UCMR5, 1 contaminant has been measured above federal EPA standards (MCL) and 1 exceeds health-based guidelines. The most significant finding is Combined Radium (226+228) at 6.73 pCi/L, which is 1.3x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 2000 through 2028. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2000-10-21","end":"2028-12-31"},"contaminants_tested":40,"contaminants_detected":14,"exceedances":1,"guideline_exceedances":1,"contaminants":[{"name":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":1.01,"unit":"ug/L","sample_date":"2026-09-15","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.0001,"health_guideline_source":"EWG Health Guideline","epa_mcl_value":0.06,"status":"below_limits","detection_limit":null},{"name":"Combined Radium (226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"legal_violation","measured_value":6.73,"unit":"pCi/L","sample_date":"2026-07-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0,"health_guideline_source":"EPA MCLG","epa_mcl_value":5,"status":"exceeds_legal_limit","detection_limit":null},{"name":"Gross Alpha","code":"4000","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":11.9,"unit":"pCi/L","sample_date":"2026-07-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0,"health_guideline_source":"EPA MCLG","epa_mcl_value":15,"status":"below_limits","detection_limit":null},{"name":"Barium","code":"BARIUM","cas_number":"7440-39-3","group":"inorganics","section":"other_detected","measured_value":0.19,"unit":"mg/L","sample_date":"2026-02-24","source":"DNR","source_scope":"source_monitoring","health_guideline_value":1,"health_guideline_source":"OEHHA PHG 2003 (hypertension endpoint)","epa_mcl_value":2,"status":"below_limits","detection_limit":null},{"name":"Fluoride (natural)","code":"FLUORIDE","cas_number":"16984-48-8","group":"inorganics","section":"other_detected","measured_value":0.635,"unit":"mg/L","sample_date":"2026-02-24","source":"DNR","source_scope":"source_monitoring","health_guideline_value":4,"health_guideline_source":"EPA MCLG","epa_mcl_value":4,"status":"below_limits","detection_limit":null},{"name":"Nitrate (as N)","code":"NITRATE","cas_number":"14797-55-8","group":"inorganics","section":"other_detected","measured_value":0.92,"unit":"mg/L","sample_date":"2026-02-24","source":"DNR","source_scope":"source_monitoring","health_guideline_value":10,"health_guideline_source":"EPA MCLG","epa_mcl_value":10,"status":"below_limits","detection_limit":null},{"name":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":4.38,"unit":"ug/L","sample_date":"2025-09-02","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.00015,"health_guideline_source":"EWG Health Guideline","epa_mcl_value":0.08,"status":"below_limits","detection_limit":null},{"name":"Arsenic","code":"ARSENIC","cas_number":"7440-38-2","group":"inorganics","section":"other_detected","measured_value":2.4,"unit":"ug/L","sample_date":"2014-07-21","source":"WQP","source_scope":"regional_groundwater","health_guideline_value":0.000004,"health_guideline_source":"OEHHA PHG","epa_mcl_value":0.01,"status":"exceeds_guideline","detection_limit":null},{"name":"Orthophosphate","code":"ORTHOPHOSPHATE","cas_number":null,"group":"other","section":"other_detected","measured_value":120,"unit":"ug/L","sample_date":"2025-10-07","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"other_detected","measured_value":0,"unit":"mg/L","sample_date":"2028-12-31","source":"EPA ECHO","source_scope":"federal_program","health_guideline_value":0.0002,"health_guideline_source":"OEHHA PHG","epa_mcl_value":null,"status":"below_limits","detection_limit":null},{"name":"Copper (90th Percentile)","code":"COPPER","cas_number":"7440-50-8","group":"lead_copper","section":"other_detected","measured_value":9.5,"unit":"ug/L","sample_date":"2026-08-21","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.3,"health_guideline_source":"OEHHA PHG","epa_mcl_value":null,"status":"below_limits","detection_limit":null},{"name":"PFBS (Perfluorobutane Sulfonate)","code":"PFBS","cas_number":"375-73-5","group":"pfas","section":"pfas","measured_value":0.7,"unit":"ng/L","sample_date":"2026-07-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"PFBA (Perfluorobutanoic Acid)","code":"PFBA","cas_number":null,"group":"pfas","section":"pfas","measured_value":0.9,"unit":"ng/L","sample_date":"2026-07-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"PFOS (Perfluorooctane Sulfonate)","code":"PFOS","cas_number":"1763-23-1","group":"pfas","section":"pfas","measured_value":0.8,"unit":"ng/L","sample_date":"2026-07-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.004,"status":"below_limits","detection_limit":null},{"name":"PFHxS (Perfluorohexane Sulfonate)","code":"PFHXS","cas_number":"355-46-4","group":"pfas","section":"pfas","measured_value":0.7,"unit":"ng/L","sample_date":"2026-07-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.01,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.01,"status":"below_limits","detection_limit":null}],"sources":[{"name":"DNR","url":"https://apps.dnr.wi.gov/dwsportalpub"},{"name":"WQP","url":"https://www.waterqualitydata.us/"},{"name":"EPA ECHO","url":"https://echo.epa.gov/"},{"name":"EPA UCMR5","url":"https://www.epa.gov/dwucmr/fifth-unregulated-contaminant-monitoring-rule"}],"pfas_combined_display":null,"well_counts":{"active":4,"retired":0,"facilities_synced_at":"2026-10-26T01:13:06.376Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":{"value":0.0704,"compounds_used":["PFHXS","PFBS"],"is_partial":true,"threshold":1,"components":[{"code":"PFHXS","value_ng_l":0.7,"hbwc_ng_l":10,"ratio":0.07},{"code":"PFBS","value_ng_l":0.7,"hbwc_ng_l":2000,"ratio":0.0004}]},"tthm_lraa":[],"haa5_lraa":[]}